1. Field of the Invention
The present invention relates to an electrical socket connector, and more particularly to a central processing unit (CPU) socket connector for electrically connecting a CPU to a printed circuit board (PCB).
2. Description of the Prior Art
Conventionally, a CPU socket connector includes a base, a cover slidably mounted on the base, a plurality of contacts received in the base, and an actuator sandwiched between the cover and the base for urging the cover to move relative to the base. The base defines an array of passageways for accommodating the contacts therein, respectively. The cover defines an array of holes corresponding to the passageways for insertion of pins of a CPU therethrough. The contacts are adapted to mechanically engage with the pins to achieve electrical engagement between the CPU and the socket connector. Precise engagement between the pins and the contacts is very important for reliable electrical transmission. Accurate engagement depends in large part on correct attachment of the cover on the base. This can be problematic in environments such as mass production facilities where various connectors having slightly different bases and covers are assembled. Mismatching of non-corresponding bases and covers can occur.
FIG. 5 shows a conventional CPU socket connector 6 as disclosed in Taiwan Pat. No. 388570. The connector 6 includes a base 62, a cover 63 slidably mounted on the base 62, a plurality of contacts 64 received in the base 62, and an actuator 65 received between the base 62 and the cover 63 for actuating the cover 63 to move relative to the base 62. The cover 63 has sidewalls 630 at opposite lateral sides thereof. The sidewalls 630 define recesses 632 therein. The base 62 forms blocks 620 corresponding to the recesses 632, respectively. The blocks 620 are slidably engaged in the recesses 632 respectively, thus mounting the cover 63 onto the base 62. However, in the electrical connector industry, a variety of connectors 6 may be manufactured, each connector 6 having a configuration similar to other of the connectors 6. In particular, the connectors 6 may have slightly different bases 62 but with the same blocks 620, and slightly different covers 63 but with the same recesses 632. No blind mating means are provided on the bases 62 or the covers 63. As a result, mismating between the bases and the covers can easily occur.
U.S. Pat. No. 5,167,515 discloses another CPU socket connector. The CPU socket connector includes a base, a cover slidably mounted on the base, a plurality of contacts secured in the base, and an actuator received between the cover and the base. The cover forms hooks at opposite lateral sides thereof. The base forms blocks corresponding to the hooks. The blocks are slidably engaged with the hooks so as to mount the cover onto the base. Neither the base nor the cover provides blind mating means. The socket connector is liable to mismating as described above. Further, CPU sockets disclosed in U.S. Pat. Nos. 5,454,727 and 5,489,217 also have this same disadvantage.
Accordingly, there is a need to provide a new CPU socket connector with a blind mating retention structure that overcomes the above-mentioned problems.
An object of the present invention is to provide a socket connector having blind mating means for ensuring correct attachment of a cover to its corresponding base.
To achieve the above object, a CPU socket connector for electrically connecting a CPU to a PCB is provided by the present invention. The CPU socket connector comprises a base, a cover slidably mounted on the base, an actuator received between the cover and the base for urging the cover to move relative to the base, and a plurality of electrical contacts received in the base. The base forms first and second blocks at opposite lateral sides thereof. The first and second blocks have different lengths along a direction of sliding of the cover on the base. The cover forms first and second side walls having different lengths along said direction, corresponding to the first and second blocks.
For the CPU socket connector of the present invention, a range of slightly different bases may be manufactured. Each base is configured with first and second blocks having unique predetermined different lengths along said direction. Correspondingly, a range of slightly different covers may be manufactured for the CPU socket connector. Each cover is configured with first and second side walls having unique predetermined different lengths along said direction. The various configurations of the first and second side walls of the covers respectively and uniquely correspond to the various configurations of the first and second blocks of the bases. Thus for each CPU socket connector, the first and second blocks of the base can only be mated with the first and second side walls of the correct corresponding cover. Mismating of the base with a non-matching cover, or vice versa, is prevented. As a result, correct mechanical and electrical engagement between the pins of the CPU and the contacts is assured.
Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: